Scotland Yard has issued a fresh appeal for information over the fatal stabbing of a Croydon man in March.

Bjorn Brown, 23, from South Norwood, who was a childhood friend of Croydon grime star Stormzy, was attacked and repeatedly stabbed by two men as he made his way down Bensham Lane in Thornton Heath on March 29. He attempted to cycle away from the scene before collapsing.

He was later found by a motorist who flagged down a passing ambulance and died of his wounds at a south London hospital five days later.

Detectives from the Metropolitan Police Homicide and Major Crime Command launched a murder investigation in March, but no arrests have been made and the case remains open.

Detective Inspector Tom Dahri, who is leading the investigation, said: “We are determined to bring those responsible for Bjorn’s death to justice. I would appeal to anyone who witnessed this, or has any information, to come forward.

“Please do not hesitate, any information you have could be vital. Members of the public came to Bjorn’s help as he lay injured, I would ask the public to continue that support by contacting police or Crimestoppers.”

The appeal comes at a time of intense scrutiny over knife crime in the borough, following the murders of 15-year-old Jermaine Goupall in August and Aren Mali, 17, in October.

Croydon Central MP Sarah Jones has called knife crime among young people an “epidemic” and a “public health crisis”. She has set up an all-party parliamentary group on the issue, and recently called for a 10-year coordinated multiagency strategy to tackle its causes. Knife crime in Croydon has doubled over the past year.

In May, Brown’s aunt, Gogglebox star Sandi Bogle, called on his killers to hand themselves in. She told the Croydon Advertiser: “What I would say to the person who did this is ‘come forward and take responsibility for your crime’.

“We are all human beings, we all bleed the same blood, we all have a passion, surely they have a conscience – so where is it?”

Anyone who witnessed the stabbing or has any information is asked to contact the incident room on 020 8721 4961 or contact police via Twitter @MetCC